Nicholas D. Gilson

Occupational sitting and health risks: a systematic review

CONTEXT Emerging evidence suggests that sedentary behavior (i.e., time spent sitting) may be negatively associated with health. The aim of this study was to systematically review the evidence on associations between occupational sitting and health risks. EVIDENCE ACQUISITION Studies were identified in March-April 2009 by literature searches in PubMed, PsycINFO, CENTRAL, CINAHL, EMBASE, and PEDro, with subsequent related-article searches in PubMed and citation searches in Web of Science. Identified studies were categorized by health outcome. Two independent reviewers assessed methodologic quality using a 15-item quality rating list (score range 0-15 points, higher score indicating better quality). Data on study design, study population, measures of occupational sitting, health risks, analyses, and results were extracted. EVIDENCE SYNTHESIS 43 papers met the inclusion criteria (21% cross-sectional, 14% case-control, 65% prospective); they examined the associations between occupational sitting and BMI (n=12); cancer (n=17); cardiovascular disease (CVD, n=8); diabetes mellitus (DM, n=4); and mortality (n=6). The median study-quality score was 12 points. Half the cross-sectional studies showed a positive association between occupational sitting and BMI, but prospective studies failed to confirm a causal relationship. There was some case-control evidence for a positive association between occupational sitting and cancer; however, this was generally not supported by prospective studies. The majority of prospective studies found that occupational sitting was associated with a higher risk of DM and mortality. CONCLUSIONS Limited evidence was found to support a positive relationship between occupational sitting and health risks. The heterogeneity of study designs, measures, and findings makes it difficult to draw definitive conclusions at this time.

Are workplace interventions to reduce sitting effective? A systematic review

OBJECTIVE To systematically review the effectiveness of workplace interventions for reducing sitting. METHODS Studies published up to April 2009 were identified by literature searches in multiple databases. Studies were included if they were interventions to increase energy expenditure (increase physical activity or decrease sitting); were conducted in a workplace setting; and specifically measured sitting as a primary or secondary outcome. Two independent reviewers assessed methodological quality of the included studies, and data on study design, sample, measures of sitting, intervention and results were extracted. RESULTS Six studies met the inclusion criteria (five randomised trials and one pre-post study). The primary aim of all six was to increase physical activity; all had reducing sitting as a secondary aim. All used self-report measures of sitting; one specifically assessed occupational sitting time; the others used measures of general sitting. No studies showed that sitting decreased significantly in the intervention group, compared with a control or comparison group. CONCLUSION Currently, there is a dearth of evidence on the effectiveness of workplace interventions for reducing sitting. In light of the growing body of evidence that prolonged sitting is negatively associated with health, this highlights a gap in the scientific literature that needs to be addressed.

Do walking strategies to increase physical activity reduce reported sitting in workplaces: a randomized control trial

BackgroundInterventions designed to increase workplace physical activity may not automatically reduce high volumes of sitting, a behaviour independently linked to chronic diseases such as obesity and type II diabetes. This study compared the impact two different walking strategies had on step counts and reported sitting times.MethodsParticipants were white-collar university employees (n = 179; age 41.3 ± 10.1 years; 141 women), who volunteered and undertook a standardised ten-week intervention at three sites. Pre-intervention step counts (Yamax SW-200) and self-reported sitting times were measured over five consecutive workdays. Using pre-intervention step counts, employees at each site were randomly allocated to a control group (n = 60; maintain normal behaviour), a route-based walking group (n = 60; at least 10 minutes sustained walking each workday) or an incidental walking group (n = 59; walking in workday tasks). Workday step counts and reported sitting times were re-assessed at the beginning, mid- and endpoint of intervention and group mean± SD steps/day and reported sitting times for pre-intervention and intervention measurement points compared using a mixed factorial ANOVA; paired sample-t-tests were used for follow-up, simple effect analyses.ResultsA significant interactive effect (F = 3.5; p < 0.003) was found between group and step counts. Daily steps for controls decreased over the intervention period (-391 steps/day) and increased for route (968 steps/day; t = 3.9, p < 0.000) and incidental (699 steps/day; t = 2.5, p < 0.014) groups. There were no significant changes for reported sitting times, but average values did decrease relative to the control (routes group = 7 minutes/day; incidental group = 15 minutes/day). Reductions were most evident for the incidental group in the first week of intervention, where reported sitting decreased by an average of 21 minutes/day (t = 1.9; p < 0.057).ConclusionCompared to controls, both route and incidental walking increased physical activity in white-collar employees. Our data suggests that workplace walking, particularly through incidental movement, also has the potential to decrease employee sitting times, but there is a need for on-going research using concurrent and objective measures of sitting, standing and walking.

Does Physical Activity Impact on Presenteeism and Other Indicators of Workplace Well-Being?

The term ‘presenteeism’ is a relatively new concept in workplace health, and has come to signify being at work despite poor health and performing below par. Presenteeism, which is potentially critical to employers, has been associated with a range of psychosocial outcome measures, such as poor mental health and employee well-being. Physical activity is a potential strategy for reducing presenteeism, and for improving the mental health of employees. This article reviews evidence on the relationships between physical activity and employee well-being and presenteeism in the workplace, and identifies directions for research in an emerging field.Electronic and manual literature searches were used to identify 20 articles that met the inclusion criteria. These included 13 intervention trials (8 randomized controlled trials, 5 comparison trials) and 7 observational studies (3 cohort, 4 cross-sectional). Outcome measures were grouped into workplace well-being, psychosocial well-being and physical well-being. Studies measured a wide variety of outcomes, with absenteeism being the most commonly assessed. Evidence indicated a positive association between physical activity and psychosocial health in employees, particularly for quality of life and emotional well-being. However, findings were inconclusive as to the role of physical activity in promoting workplace well-being. Only one study reported on presenteeism, with mixed evidence for outcomes.This article indicates that physical activity and employee psychosocial health are positively related, but there is limited evidence of a relationship between physical activity and presenteeism. A standardized definition of presenteeism and an appropriate evaluation tool are key research priorities if the complex relationships between physical activity and workplace well-being are to be better understood.

Participatory Workplace Interventions Can Reduce Sedentary Time for Office Workers—A Randomised Controlled Trial

Background Occupational sedentary behaviour is an important contributor to overall sedentary risk. There is limited evidence for effective workplace interventions to reduce occupational sedentary time and increase light activity during work hours. The purpose of the study was to determine if participatory workplace interventions could reduce total sedentary time, sustained sedentary time (bouts >30 minutes), increase the frequency of breaks in sedentary time and promote light intensity activity and moderate/vigorous activity (MVPA) during work hours. Methods A randomised controlled trial (ANZCTR number: ACTN12612000743864) was conducted using clerical, call centre and data processing workers (n = 62, aged 25–59 years) in 3 large government organisations in Perth, Australia. Three groups developed interventions with a participatory approach: ‘Active office’ (n = 19), ‘Active Workstation’ and promotion of incidental office activity; ‘Traditional physical activity’ (n = 14), pedometer challenge to increase activity between productive work time and ‘Office ergonomics’ (n = 29), computer workstation design and breaking up computer tasks. Accelerometer (ActiGraph GT3X, 7 days) determined sedentary time, sustained sedentary time, breaks in sedentary time, light intensity activity and MVPA on work days and during work hours were measured before and following a 12 week intervention period. Results For all participants there was a significant reduction in sedentary time on work days (−1.6%, p = 0.006) and during work hours (−1.7%, p = 0.014) and a significant increase in number of breaks/sedentary hour on work days (0.64, p = 0.005) and during work hours (0.72, p = 0.015); there was a concurrent significant increase in light activity during work hours (1.5%, p = 0.012) and MVPA on work days (0.6%, p = 0.012). Conclusions This study explored novel ways to modify work practices to reduce occupational sedentary behaviour. Participatory workplace interventions can reduce sedentary time, increase the frequency of breaks and improve light activity and MVPA of office workers by using a variety of interventions. Trial Registration Australian New Zealand Clinical Trials Registry ACTN12612000743864.

Objectively measured sedentary behavior and physical activity in office employees: relationships with presenteeism.

Objective: Employee presenteeism is the extent to which health conditions adversely affect at-work productivity. Given the links between health and activity, this study examined associations between objectively measured physical activity, sedentary behavior, and presenteeism. Methods: Participants were 108 office employees (70% women, mean age 40.7 ± 11.2 years). Activity was measured using ActiGraph GT3X+ accelerometers to determine sedentary (⩽150 counts) and light (151 to 1689 counts) activity; presenteeism with the Work Limitations Questionnaire. Results: Fifty-seven percent of time was spent in sedentary behavior and 38% in light activity. The median Work Limitations Questionnaire Index was 4.38; 6% of participants reported at least moderate impairment. Significant associations were reported for time spent in sedentary behavior before/after work (odds ratio [OR] = 2.58; 95% CI: 1.08 to 6.20) and in light activity, overall (OR = 0.43; 95% CI: 0.19 to 0.97) and during workday lunch hours (OR = 0.34; 95% CI: 0.15 to 0.77), and presenteeism. Conclusions: Future studies should seek greater variation in employee levels of activity and presenteeism to confirm these relationships.

Validation of a Novel, Objective Measure of Occupational Sitting

Validation of a Novel, Objective Measure of Occupational Sitting: Gemma C. RYDE, et al. St Lucia Campus, School of Human Movement Studies, The University of Queensland, Australia—

Cost effectiveness of interventions to improve moderate physical-activity: A study in nine UK sites

Objective: With growing concerns to establish the value for returns on public health investment, there is a need to identify cost-effective physical activity interventions. This study measured change in moderate physical activity (MPA) in seven community-based intervention types, costs and cost-effectiveness of the interventions, and possible explanations for cost variation. Design: Between 2004 and 2006, pre- and post-intervention assessments identified demographics and MPA levels, and quarterly interviews with intervention managers identified key implementation costs. Setting: Nine sites across the UK. Method: MPA was collected using self-report measures. MPA categories (sedentary, lightly, moderately, highly active) were assigned at pre- and post-intervention. Differences between pre- and post-intervention scores identified MPA change (median metabolic equivalent (MET)-minutes/week) in completers. Cost, attendance and activity data were combined to estimate the average monthly implementation cost, cost per participant attending interventions, and the cost per completer improving MPA category. An economic model was built to estimate the cost per Quality Adjusted Life Year (QALY) gained and potential savings to the National Health Service (NHS). Results: Demographics (n = 984) show that those who engaged with the interventions were predominantly white, British older females. In completers (N = 1,051), 37.9 per cent improved at least one MPA category. The cost per completer improving MPA category ranged from c£260 to c£2,786 (N = 1000). The cost per QALY gained from intervention types ranged from c£47 to c£509, which was below the £20,000 threshold implicit in National Institute for Health and Clinical Excellence (NICE) decisions. Future cost savings to the NHS per intervention participant ranged from c£769 to c£4,891. In the case of each of the interventions, this saving per participant exceeds the implementation cost per participant, which ranged from c£55 to c£3,420 (N = 6940). Conclusions: MPA interventions are cost-effective.

Patterns of Impact Resulting from a ‘Sit Less, Move More’ Web-Based Program in Sedentary Office Employees

Purpose Encouraging office workers to ‘sit less and move more’ encompasses two public health priorities. However, there is little evidence on the effectiveness of workplace interventions for reducing sitting, even less about the longer term effects of such interventions and still less on dual-focused interventions. This study assessed the short and mid-term impacts of a workplace web-based intervention (Walk@WorkSpain, W@WS; 2010-11) on self-reported sitting time, step counts and physical risk factors (waist circumference, BMI, blood pressure) for chronic disease. Methods Employees at six Spanish university campuses (n=264; 42±10 years; 171 female) were randomly assigned by worksite and campus to an Intervention (used W@WS; n=129; 87 female) or a Comparison group (maintained normal behavior; n=135; 84 female). This phased, 19-week program aimed to decrease occupational sitting time through increased incidental movement and short walks. A linear mixed model assessed changes in outcome measures between the baseline, ramping (8 weeks), maintenance (11 weeks) and follow-up (two months) phases for Intervention versus Comparison groups. Results A significant 2 (group) × 2 (program phases) interaction was found for self-reported occupational sitting (F[3]=7.97, p=0.046), daily step counts (F[3]=15.68, p=0.0013) and waist circumference (F[3]=11.67, p=0.0086). The Intervention group decreased minutes of daily occupational sitting while also increasing step counts from baseline (446±126; 8,862±2,475) through ramping (+425±120; 9,345±2,435), maintenance (+422±123; 9,638±3,131) and follow-up (+414±129; 9,786±3,205). In the Comparison group, compared to baseline (404±106), sitting time remained unchanged through ramping and maintenance, but decreased at follow-up (-388±120), while step counts diminished across all phases. The Intervention group significantly reduced waist circumference by 2.1cms from baseline to follow-up while the Comparison group reduced waist circumference by 1.3cms over the same period. Conclusions W@WS is a feasible and effective evidence-based intervention that can be successfully deployed with sedentary employees to elicit sustained changes on “sitting less and moving more”.

Desk-Based Occupational Sitting Patterns: Weight-Related Health Outcomes

BACKGROUND Prolonged, uninterrupted sitting time is associated with poor health outcomes. As most sitting time occurs at work, accurate, objective measurement of occupational sitting patterns is required to fully understand its effects on employee health. PURPOSE The purpose of this study was to examine associations of desk-based sitting patterns with waist circumference (WC) and BMI. METHODS Participants were full-time, office-based employees (N=105; mean age 40.9±11.5 years; BMI 26.1±3.9; 65% women). Sitting patterns (total desk-based sitting time and number of times employees got up from their desk) were assessed for 5 days using an objective measure of desk-based sitting: the sitting pad. WC, height, and weight were measured, and BMI was calculated. Associations of sitting patterns with WC and BMI were tested using logistic regression models. Data were collected and analyzed in 2011-2012. RESULTS Those with high levels of sitting time at their desk were 2.7 times (95% CI=1.3, 6.3) more likely to have WC ≥94 cm (men) and ≥80 cm (women), and 9.0 times (95% CI=1.9, 41.9) more likely to have BMI ≥30 than those with lower sitting time. There were no associations between the number of times employees got up from sitting at their desk and WC or BMI. CONCLUSIONS High levels of desk-based sitting time were associated with an increased likelihood of negative weight-related health outcomes, whereas frequency of getting up from sitting at the desk was not.